'Abdullah b. Ka'b reported that his father Ka'b narrated to him that Messenger of Allah ﷺ used to eat with three fingers and when he had finished (eating), he licked them.
أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَأْكُلُ بِثَلاَثِ أَصَابِعَ فَإِذَا فَرَغَ لَعِقَهَا